CN220142744U - Concrete sewage filtering device and system - Google Patents

Abstract

The utility model relates to a concrete sewage filtering device and system, in particular to the technical field of recycling of premixed concrete sewage. Comprises a shell, a filtering mechanism and a secondary filtering device; the top end of the shell is provided with a sewage inlet, the tail end of the shell is provided with a sand outlet, and the bottom of the shell is provided with at least one drainage channel; the filter screen assembly comprises a primary screen and a secondary screen, the primary screen and the secondary screen are sequentially arranged on the stirring unit along the direction from the sewage inlet to the sand outlet, the secondary filter device is arranged at the bottom of the primary screen, and a diversion channel is arranged between the primary screen and the secondary filter device. According to the utility model, the primary screen and the secondary screen are arranged, so that the pore size of the primary screen is large, part of fine sand can flow into the secondary filter device through the primary screen, the filtering pressure of the front section screen of the filter device is reduced, the utilization rate of the rear section screen of the sewage filter device is improved, the service life of the screen assembly is ensured, the filtering efficiency is improved, and the mud-water separation cost is reduced.

Description

Concrete sewage filtering device and system

Technical Field

The utility model relates to the technical field of premixed concrete sewage recycling, in particular to a concrete sewage filtering device and a system.

Background

In the premixed concrete field, the transportation of concrete is all transported through the concrete mixing transport vechicle, and the transport vechicle is in transportation process, and the automobile body is stained with the concrete easily, also needs regularly to wash in the jar simultaneously, comes to wash the concrete of remaining on the transport vechicle, prevents the concrete caking of the inside and outside of follow-up transport vechicle, and then influences the normal use of transport vechicle.

In a concrete factory, a large amount of sewage mixed with concrete fine sand can be generated in the flushing process of a transport vehicle, and the sewage cannot be discharged at will, so that the problems of pipeline blockage, environmental pollution and the like are prevented, and mud-water separation is needed. The mud-water separation device on the market at present carries out mud-water filtration with single filter screen generally, and because sewage gets into mud-water separation device first section, and sewage flow is big, and mud-water separation device anterior segment filter screen filtration volume is too big, leads to the fact the filter screen to block up in anterior segment filter screen department easily, makes filter screen life-span shorten, and the posterior segment filter screen utilization ratio is low, leads to current mud-water separation device filtration inefficiency, and appears needing to change the filter screen often easily, has increased mud-water separation cost.

Disclosure of Invention

The utility model provides a concrete sewage filtering device, which aims to solve the technical problems that the waste water generated by cleaning a concrete vehicle in a premixed concrete factory is difficult to treat, the separation efficiency of a current mud-water separation device is low, a filter screen needs to be frequently replaced, and the mud-water separation cost is high.

In order to solve the technical problems, the technical scheme of the utility model is as follows:

a concrete sewage filtering device comprises a shell, a filtering mechanism and a secondary filtering device; the top end of the shell is provided with a sewage inlet, the tail end of the shell is provided with a sand outlet, and the bottom of the shell is provided with at least one drainage channel; the filtering mechanism comprises a stirring unit and a filter screen assembly, the stirring unit is arranged between the sewage inlet and the sand outlet, and the filter screen assembly is arranged around the periphery of the stirring unit; the stirring unit comprises a driving motor and a spiral rotating rod; the driving motor is in driving connection with the spiral rotating rod, and a spiral sand filtering channel is formed between the sewage inlet and the sand outlet; the filter screen assembly comprises a primary screen and a secondary screen, the primary screen and the secondary screen are sequentially arranged on the stirring unit along the direction from the sewage inlet to the sand outlet, the secondary filter device is arranged at the bottom of the primary screen, and a diversion channel is arranged between the primary screen and the secondary filter device.

Further, the surfaces of the primary screen and the secondary screen are uniformly provided with small drainage holes for separating fine sand and water in sewage, and the aperture of the small drainage holes of the primary screen is larger than that of the secondary screen.

Further, the sewage inlet of the casing is arranged at the top of the primary screening filter screen, the sand outlet is arranged at the bottom of the casing, the sand outlet is arranged obliquely downwards, and water stop plates are respectively arranged at the bottom positions of the casing between the primary screening filter screen and the secondary screening filter screen and at the bottom positions of the sand outlet.

Further, the drainage channel is arranged at the bottom of one end of the casing close to the sand outlet; the bottom of the inner side of the shell is obliquely arranged towards the water leakage port of the water drainage channel.

Further, the filter screen assembly further comprises a framework, wherein the framework is of a cylindrical structure; the framework is fixedly arranged in the shell, and the primary filter screen and the secondary filter screen are detachably arranged on the framework.

Further, the filter screen assembly comprises two groups of cleaning devices, wherein the two groups of cleaning devices are arranged on the inner wall of the machine shell and are respectively arranged on two sides of the filter screen assembly.

Further, two spiral blades are arranged on the spiral rotating rod, and the two blades are in spiral interaction and form a spiral sand filtering channel.

Further, the secondary filter device comprises a second filter mechanism arranged between an inlet and an outlet of the secondary filter device, one end of the diversion channel is connected with a water outlet at the position below the primary screen in the shell, and the other end of the diversion channel is arranged at the inlet of the second filter mechanism.

Further, the second filtering mechanism comprises a second stirring unit and a fine sand filter screen, the second stirring unit is arranged between the inlet of the secondary filtering device and the sand outlet, and the fine sand filter screen is arranged around the periphery of the stirring unit.

The utility model also provides a concrete sewage filtering system which comprises a stirrer and the concrete sewage filtering device; the inlet of the mixer is connected with the drainage channel of the concrete sewage filtering device.

According to the utility model, the concrete wastewater filtering device is used for treating wastewater generated after the concrete cleaning vehicle is separated by the sand-stone separator, and the finer fine sand in the wastewater is separated for the second time, so that the channel is prevented from being blocked in the subsequent wastewater conveying process. This filter equipment is through setting up primary screen, second grade filter screen, and primary screen aperture is big, makes partial fine sand flow into second grade filter equipment through the primary screen, reduces filter equipment anterior segment filter screen's filtration pressure, simultaneously, flows through second grade filter screen, second grade filter equipment's sewage, can assemble the fine sand after the separation together at the play sand mouth under the filtration of agitator unit and filter screen subassembly, makes fine sand can reuse, reduces the risk that sewage low reaches blockked up simultaneously. The sewage filtering mode can improve the utilization rate of the filter screen at the rear end of the sewage filtering device, ensure the service life of the filter screen component, improve the filtering efficiency and reduce the mud-water separation cost.

Drawings

Fig. 1 is a perspective view of a concrete sewage filtering apparatus according to an embodiment of the present utility model.

Fig. 2 is an internal cross-sectional view of a concrete sewage filtering apparatus in an embodiment of the present utility model.

Fig. 3 is a schematic structural view of a filtering mechanism of the concrete sewage filtering device in the embodiment of the utility model.

Fig. 4 is a schematic diagram illustrating an internal structure of a casing according to an embodiment of the present utility model.

Wherein:

the sewage treatment device comprises a shell 10, a sewage inlet 11, a sand outlet 12, a drainage channel 13, a cleaning device 14 and a water stop plate 15;

the filter mechanism is 20, the stirring unit is 21, the filter screen component is 22, the spiral rotating rod is 211, the primary filter screen is 221, the secondary filter screen is 222, and the framework is 223;

the second filtering device is 30, and the second filtering mechanism is 31;

the frame is 40.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present utility model more apparent, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. The described embodiments are some, but not all, embodiments of the utility model.

Thus, the following detailed description of the embodiments of the utility model, as presented in the figures, is not intended to limit the scope of the utility model, as claimed, but is merely representative of selected embodiments of the utility model. All other embodiments, based on the embodiments of the utility model, which are apparent to those of ordinary skill in the art without inventive faculty, are intended to be within the scope of the utility model.

Example 1

Fig. 1 is a perspective view showing a concrete sewage filtering apparatus in the present embodiment; fig. 2 shows an internal cross-sectional view of the concrete sewage filtering device in the present embodiment; fig. 3 shows a schematic structural view of the filtering mechanism 20 of the concrete wastewater filtering apparatus in the present embodiment.

In view of the fact that more fine sand is contained in the sewage generated after the concrete carrier vehicle is cleaned through the sand-stone separator at present, the rotation of stirring blades in sedimentation is used for preventing fine sand sedimentation in the conventional industry, the sedimentation of fine sand in a pipeline cannot be prevented, the pipeline is blocked, regular cleaning is needed, and the production is seriously affected, and the technical problem of high labor cost of sewage treatment is caused. As shown in fig. 1-3, this embodiment provides a concrete sewage filtering device, which filters out fine sand in sewage by flowing the sewage through a filtering mechanism 20 in a casing 10, and drives the fine sand to flow out from a sand outlet 12 by stirring by a stirring unit 21, so that the fine sand in the sewage can be reused, and meanwhile, the subsequent treatment and transportation of the sewage can be ensured to be smooth, and the problem of channel blockage can not occur.

Specifically, in terms of structure, the concrete sewage filtering device of this embodiment includes a casing 10 and a filtering mechanism 20, where the casing 10 is a casing of the concrete sewage filtering device, and mainly plays a role in supporting and protecting the internal filtering mechanism 20 and providing a circulation channel for sewage, and the inside of the casing is hollow, and water flow can enter through a sewage inlet 11 on the casing 10 and circulate to a sand outlet 12 through a hollow channel inside the casing. The filtering mechanism 20 is used for primarily separating the sewage flowing through the casing 10, discharging part of fine sand into the secondary filtering device 30 after primary screening, preventing the filter screen from being blocked, filtering the mixed gravel through the secondary filter screen 222, and filtering the mixed gravel by the stirring unit 21, and separating the fine sand and the filtered sewage after filtering through the filter screen assembly 22 by flowing out of the sand outlet 12 and the drainage channel 13 respectively. As a supplement, the fine sand separated later is discharged and accumulated in the sand storage tank through the sand outlet 12 and can be used for subsequent recycling; the sewage flows through the drainage channel 13 and is transported to the next treatment station for recycling under the stirring of the stirring blade of the sedimentation tank. Similarly, the sewage with fine gravel flowing in after the primary screening in the secondary filtering device 30 is filtered by the secondary filtering device 30, and the fine gravel is separated and then sent into the sand storage tank. The treated water can be used for concrete production or cleaning of a mixer truck, so that water resource circulation is achieved, enterprise cost is reduced, and resource waste is reduced.

In terms of connection relation of parts, two ends of the casing 10 are respectively provided with a sewage inlet 11 and a sand outlet 12, and at least one drainage channel 13 is arranged at the bottom of the casing 10, wherein the sewage inlet 11 is used as a feed inlet of a concrete sewage filtering device, and the sand outlet 12 and the drainage device are used for separating fine sand and water after filtering and separating. The filter mechanism 20 specifically includes a stirrer unit 21 and a filter assembly 22, where the filter assembly 22 is disposed on the periphery of the stirrer unit 21, and the filter assembly 22 is fixed on the casing 10 and does not contact with the spiral rod 211 of the stirrer unit 21. The stirring unit 21 comprises a driving motor and a spiral rotating rod 211, wherein the driving motor is in driving connection with the spiral rotating rod 211 and is used for driving the spiral rotating rod 211 to rotate, and the spiral rotating rod 211 rotates to further ensure sand-water separation in sewage.

Specifically, two spiral blades are disposed on the spiral rotating rod 211, the two blades are in spiral interaction, a spiral sand filtering channel is formed on the rotation cambered surface of the spiral rotating rod 211, sewage entering the casing 10 passes through the spiral sand filtering channel, sand-water separation is achieved under the stirring of the spiral rotating rod 211, and water can flow to the drainage channel 13 below the casing 10 through the filter screen assembly 22. More specifically, the inlet and outlet of the spiral sand filtering channel in this embodiment correspond to the sewage inlet 11 and the sand outlet 12 of the casing 10, respectively, that is, after sewage enters the casing 10 from the sewage inlet 11, the sewage flows to the spiral sand filtering channel of the filtering mechanism 20 along the channel of the sewage inlet 11, and is filtered by the primary screen 221, the sewage with fine sand is introduced into the secondary filtering device 30 through the diversion channel, and after the coarse sand and the unseparated sewage are filtered and separated by the secondary screen 222, the filtered gravel is discharged from the sand outlet 12. As another important component of the filter mechanism 20, a screen assembly 22 is mounted within the housing 10 and around the periphery of the helical sand filtering path of the mixer housing 10, the screen assembly 22 is not in contact with the rotating screw rod 211, its diameter is matched to the rotating diameter of the screw rod 211, and the screw rod 211 carries filtered sand in the screen assembly 22 toward the sand outlet 12 and separates it from the sand outlet 12.

It should be noted that, the casing 10 is disposed obliquely with respect to the ground, after sewage enters the casing 10, the sewage is driven by gravity and the stirring unit 21 to move toward the sand outlet 12, after passing through the primary screen 221, water in the sewage is filtered out from the screen assembly 22 and flows to the bottom of the casing 10 during stirring, and is discharged from the drainage channel 13, gravel is left in the secondary screen 222, and is gradually moved toward the sand outlet 12 under the driving of the spiral rotating rod 211 and the blades, and finally the casing 10 is separated from the sand outlet 12.

Referring to fig. 4, in the present embodiment, the casing 10 is further provided with a cleaning device 14 above the filtering mechanism 20, and the cleaning device 14 includes a nozzle for timing spraying clean water to the filter screen assembly 22, so as to clamp fine sand on the filter screen assembly 22, and prevent the filter screen assembly 22 from being blocked by deposition. In a specific arrangement, the cleaning device 14 is provided with two sets, and the two sets of cleaning devices 14 are mounted on the inner wall of the housing 10 and are disposed on either side of the screen assembly 22. In addition, preferably, the casing is provided with a water-stop plate 15 at a bottom position between the primary screen 221 and the secondary screen 222 and at a bottom position of the sand outlet, and the water-stop plate 15 at a bottom position between the primary screen 221 and the secondary screen 222 is mainly used for enabling sewage with fine sand filtered by the primary screen 221 to smoothly enter the secondary filter device 30 through the diversion channel without being erroneously introduced into the drainage channel for discharge. The water-stop plate 15 at the bottom of the sand outlet is mainly used for separating the water separated by the secondary filter screen 222, preventing the water from entering the sand outlet again, and discharging the water from the water discharge channel at the bottom to realize subsequent sewage treatment.

The advantage of this embodiment lies in, and this embodiment produces sewage through concrete sewage filter equipment to washing concrete vehicle after the grit separating centrifuge separation, carries out secondary separation with finer fine sand in the sewage, avoids the in-process to follow-up sewage transportation to the passageway jam. This filter equipment is through setting up primary screen 221, second grade filter screen 222, and primary screen 221 aperture is big, makes some fine sand flow into second grade filter equipment 30 through primary screen 221, reduces the filtration pressure of filter equipment anterior segment filter screen, simultaneously, flows through second grade filter screen 222, second grade filter equipment 30's sewage, can assemble the fine sand after the separation together at the play sand mouth under the filtration of agitator unit and filter screen subassembly, makes fine sand can reuse, reduces the risk that the sewage low reaches was blocked up simultaneously. The sewage filtering mode can improve the utilization rate of the filter screen at the rear end of the sewage filtering device, ensure the service life of the filter screen component, improve the filtering efficiency and reduce the mud-water separation cost.

Example two

The present embodiment also provides a concrete sewage filtering device, which includes a housing 10, a filtering mechanism 20 and a secondary filtering device 30, wherein a sewage inlet 11 is provided at the top end of the housing 10, a sand outlet 12 is provided at the end, and at least one drainage channel 13 is provided at the bottom of the housing 10. The filter mechanism 20 comprises a stirrer set 21 and a filter screen assembly 22, wherein the stirrer set 21 is arranged between the sewage inlet 11 and the sand outlet 12, and the filter screen assembly 22 is arranged around the periphery of the stirrer set 21. The agitator unit 21 includes a driving motor and a spiral rotating rod 211, and the driving motor is in driving connection with the spiral rotating rod 211, and forms a spiral sand filtering passage between the sewage inlet 11 and the sand outlet 12. The filter screen assembly 22 comprises a primary filter screen 221 and a secondary filter screen 222, the primary filter screen 221 and the secondary filter screen 222 are sequentially arranged on the mixer set 21 along the direction from the sewage inlet 11 to the sand outlet 12, the secondary filter device 30 is arranged at the bottom of the primary filter screen 221, and a diversion channel is arranged between the primary filter screen 221 and the secondary filter device 30.

Specifically, the present embodiment is different from the first embodiment in that the present embodiment further provides a specific implementation manner.

Referring to fig. 1-3, in this embodiment, the surfaces of the primary filter screen 221 and the secondary filter screen 222 are uniformly provided with small drainage holes for separating fine sand from water in the sewage, and the aperture of the small drainage holes of the primary filter screen 221 is larger than that of the secondary filter screen 222. The advantage of this arrangement is that when the contaminated water enters the filter mechanism 20, it first passes through the primary screen 221 and part of the contaminated water and fine gravel passes through the drainage apertures of the primary screen 221 before entering the secondary filter device 30, preventing the secondary screen 222 from being blocked by the subsequent fine gravel.

As a preferable example of this embodiment, the sewage inlet 11 of the casing 10 is disposed at the top of the casing 10, the sand outlet 12 is disposed at the bottom of the casing 10, and the sand outlet 12 is disposed obliquely downward. The sand outlet 12 is specifically communicated with an external sand storage tank, and after fine sand filtered out after sewage flows through the casing 10 enters the sand storage tank through the sand outlet 12, the recycling of the follow-up fine sand is facilitated. More preferably, the method further comprises the steps of,

in some embodiments, the drainage channel 13 of the casing 10 of the present embodiment is disposed near the bottom of the sand outlet 12, and of course, as shown in fig. 2, the drainage channel 13 is disposed at the corresponding bottom of the secondary screen 222. Of course, in order to ensure smooth drainage, in some embodiments, the bottom end of the casing 10 is provided as an inclined surface inclined toward the drainage channel 13. It should be noted that the casing 10 may be supported on a preset ground by a base, which is not limited in detail in the drawings in the present utility model, but the drain channel 13 is disposed obliquely downward from the bottom of the casing 10 to one side. Preferably, the drain channel 13 in this embodiment is inclined, and the channel width is gradually reduced. In order to ensure that water in the casing 10 smoothly flows out of the drainage channel 13, an inclined lug is arranged at the bottom of the inner side of the casing 10, and the inclined angle is inclined from other places to the water outlet of the drainage channel 13, so that the filtered water can smoothly enter the drainage channel 13.

In terms of the filtering mechanism 20, the spiral rotating rod 211 of this embodiment includes two spiral blades, which are spirally interacted to form a spiral sand filtering channel, and it is noted that the two blades are respectively continuous blades, and the two blades are alternately spiral to form two channels on the spiral rotating rod 211, when sewage enters, after stirring, separated fine sand can be gradually driven to the sand outlet 12 to realize sand.

On the other hand, the filter screen assembly 22 comprises a framework 223 and a filter screen assembly 22, wherein the framework 223 is fixedly arranged in the machine shell 10, and the primary filter screen 221 and the secondary filter screen 222 are detachably arranged on the framework 223, so that the filter screen assembly 22 can be easily detached in a slicing manner when the filter mechanism 20 needs to be cleaned, and cleaning or replacement can be easily realized. Ensuring the cleanliness of the interior of the cabinet 10. More specifically, the skeleton 223 in this embodiment adopts a cylindrical structure, so that the skeleton 223 can be surrounded on the periphery of the stirring unit 21, and gaps between the filter screen assembly 22 and the stirring unit 21 are reduced, so that fine sand is not easy to deposit on the filter screen assembly 22. More specifically, the skeleton 223 may be mounted in the casing 10 by means of a snap fit or adhesive, and has a diameter that matches the diameter of the circumference of rotation of the screw blade 212 of the mixer assembly 21 when in operation.

Preferably, the secondary filter device 30 includes a second filter mechanism 31 disposed between the inlet and the outlet of the secondary filter device 30, and the diversion channel has one end connected to a drain opening in the housing at a position below the primary screen 221 and the other end disposed at the inlet of the second filter mechanism 31. The second filtering mechanism 31 is mainly used for secondary filtering of sewage with fine sand entering the secondary filtering device 30. Specifically, the second filtering mechanism 31 includes a second stirring unit and a fine sand filter screen, where the second stirring unit is similar to the stirring unit in structure, and is mainly used for stirring fine sand attached to the fine sand filter screen after filtering, driving the fine sand to flow to the outlet of the secondary filtering device 30, and finally flowing out from the secondary filtering device 30.

In this embodiment, the second stirring unit is disposed between the inlet of the secondary filtering device 30 and the sand outlet, and the fine sand filter screen is disposed around the periphery of the stirring unit, where the aperture of the water draining small hole on the fine sand filter screen is smaller than the aperture on the primary screen 221.

Preferably, the casing 10 of the present embodiment has a cylindrical structure, and the casing 10 may be formed by splicing a plurality of metal sheets.

Preferably, the sewage treatment apparatus of this embodiment further includes a frame 40, where the frame 40 is mainly used to support a casing of the sewage treatment apparatus, and it should be noted that a sand outlet in the casing of the sewage treatment apparatus is disposed obliquely downward along a horizontal plane, and a casing of the secondary filtering apparatus 30 is disposed obliquely downward along the horizontal plane toward another direction.

The benefit of this embodiment lies in, this embodiment separates more fine sand in the sewage through filtering mechanism 20 to separate sand and water through sand outlet 12 and drainage channel 13 respectively, thereby avoid follow-up sewage circulation processing in-process fine sand to cause the jam at passageway or mixer, fine sand and water after the separation can carry out the reuse through different modes, realizes the reuse of resource when avoiding the passageway to block up, effectively reduces manufacturing cost and the cost of labor of enterprise.

Example III

The present embodiment provides a concrete sewage filtering system, which comprises a mixer and a concrete sewage filtering device, wherein an inlet of the mixer is connected with a drainage channel 13 of the concrete sewage filtering device. The concrete sewage filtering device comprises a casing 10, a filtering mechanism 20 and a secondary filtering device 30, wherein the top end of the casing 10 is provided with a sewage inlet 11, the tail end of the casing is provided with a sand outlet 12, and the bottom of the casing 10 is provided with at least one drainage channel 13. The filter mechanism 20 comprises a stirrer set 21 and a filter screen assembly 22, wherein the stirrer set 21 is arranged between the sewage inlet 11 and the sand outlet 12, and the filter screen assembly 22 is arranged around the periphery of the stirrer set 21. The agitator unit 21 includes a driving motor and a spiral rotating rod 211, and the driving motor is in driving connection with the spiral rotating rod 211, and forms a spiral sand filtering passage between the sewage inlet 11 and the sand outlet 12. The filter screen assembly 22 comprises a primary filter screen 221 and a secondary filter screen 222, the primary filter screen 221 and the secondary filter screen 222 are sequentially arranged on the mixer set 21 along the direction from the sewage inlet 11 to the sand outlet 12, the secondary filter device 30 is arranged at the bottom of the primary filter screen 221, and a diversion channel is arranged between the primary filter screen 221 and the secondary filter device 30.

More specifically, the concrete sewage filtering system of the embodiment adopts the concrete sewage filtering device of the first embodiment or the second embodiment, and a large amount of fine sand in sewage is separated through the concrete sewage filtering device, so that the blocking risk in the subsequent sewage recycling and conveying process is avoided.

In the description of the present utility model, it should be understood that the terms "orientation" or "positional relationship" are based on the orientation or positional relationship shown in the drawings, and are merely for convenience of description and to simplify the description, rather than to indicate or imply that the apparatus or elements referred to must have a particular orientation, be constructed and operate in a particular orientation, and therefore should not be construed as limiting the utility model.

While the utility model has been described in conjunction with the specific embodiments above, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, all such alternatives, modifications, and variations are included within the spirit and scope of the following claims.

Claims (10)

1. The concrete sewage filtering device is characterized by comprising a shell, a filtering mechanism and a secondary filtering device; the top end of the shell is provided with a sewage inlet, the tail end of the shell is provided with a sand outlet, and the bottom of the shell is provided with at least one drainage channel; the filtering mechanism comprises a stirring unit and a filter screen assembly, the stirring unit is arranged between the sewage inlet and the sand outlet, and the filter screen assembly is arranged around the periphery of the stirring unit; the stirring unit comprises a driving motor and a spiral rotating rod; the driving motor is in driving connection with the spiral rotating rod, and a spiral sand filtering channel is formed between the sewage inlet and the sand outlet; the filter screen assembly comprises a primary screen and a secondary screen, the primary screen and the secondary screen are sequentially arranged on the stirring unit along the direction from the sewage inlet to the sand outlet, the secondary filter device is arranged at the bottom of the primary screen, and a diversion channel is arranged between the primary screen and the secondary filter device.

2. The concrete sewage filtering device according to claim 1, wherein the surfaces of the primary screen and the secondary screen are uniformly provided with small drainage holes for separating fine sand and water in sewage, and the aperture of the small drainage holes of the primary screen is larger than that of the secondary screen.

3. The concrete wastewater filtering device according to claim 1, wherein the wastewater inlet of the housing is arranged at the top of the primary screen, the sand outlet is arranged at the bottom of the housing, the sand outlet is arranged obliquely downwards, and water-stop plates are respectively arranged at the bottom positions of the housing between the primary screen and the secondary screen and at the bottom positions of the sand outlet.

4. The concrete sewage filtering device according to claim 1, wherein the drainage channel is arranged at the bottom of the casing near one end of the sand outlet; the bottom of the inner side of the shell is obliquely arranged towards the water leakage port of the water drainage channel.

5. The concrete wastewater filtration device of claim 1, wherein the screen assembly further comprises a skeleton, the skeleton being a cylindrical structure; the framework is fixedly arranged in the shell, and the primary filter screen and the secondary filter screen are detachably arranged on the framework.

6. The concrete wastewater filtering device according to claim 1, further comprising two cleaning devices, wherein two groups of the cleaning devices are arranged on the inner wall of the casing, and the two cleaning devices are respectively arranged on two sides of the filter screen assembly.

7. The concrete wastewater filtering device according to claim 1, wherein two spiral blades are arranged on the spiral rotating rod, and the two spiral blades are in spiral interaction and form a spiral sand filtering channel.

8. The concrete wastewater filter apparatus of claim 1 wherein the secondary filter apparatus includes a second filter mechanism disposed between the inlet and the outlet of the secondary filter apparatus, and wherein one end of the diversion channel is connected to a drain opening in the housing at a location below the primary screen and the other end is disposed at the inlet of the second filter mechanism.

9. The concrete wastewater filtration device of claim 8, wherein the second filtration mechanism comprises a second agitator assembly disposed between the secondary filtration device inlet and the sand outlet, and a fine sand screen disposed around the agitator assembly.

10. A concrete sewage filtration system comprising a mixer and the concrete sewage filtration device of any one of claims 1-9; the inlet of the mixer is connected with the drainage channel of the concrete sewage filtering device.